For creating the number grid, for example, the straight-forward method I was using for a 9x9(basically trial and error) isn't practical anymore.

It also looks like the approach of creating a puzzle with a certain cage distribution, then solvingit to see if it has one solution (and how much effort that takes) doesn't work anymore: so farI always end up with either "fill it in" puzzles that are too easy, or ones that take too long to solve